This study was conducted to compare the effects of perilla oil or corn lipid peroxidation and eicosanoid productions. Which are associated with the promotion of carcinogenesis. In liver or blood in rats. Male Sprague-Dawley weaning rats were fed
on
semisynthetic diets containing 15% (W/W) beef fat (BF). Corn oil (CO) or perilla oil (PO) Three weeks after. the half of rats in each group were injected with a single dose of 50mg 2-acetylaminofluorene (AAF)/Kg BW. tepatocarcinogen,
intraperitoneally 3
times at 2-day interval and all of the rats were sacrificed after 8 weeks from the first injection.
The rats fed on different dietary fats without 2-AAF treatment had not different MDA produc-tion and conjugated diene content in liver microsome. CO+AAF group had significantly higher conjugated diene content than BF+AAF and PO+AAF groups. and
lower
glucose-6 phosphatase activity than BF+AAF group. But PO+AAF had similar conjugated diene content to BF+AAF group. and significantly lower MDA production than BF+AAF and CO+AAF groups. The hepatic mocrosomal lipid peroxidation was slightly
greater
in CO
group than in PO group. though perilla oil (P/S=9.67) has much more polyunsaturated fatty acids than corn oil (P/S=2.92) PG E2 level in liver and TXB2 level in plasma were significantly higher in CO group than in BF and PO groups. TX B2 level was
lowered in CO and BF groups by 2-AAF treatment.
These results reach to the conclusion that the type of dietary fatty acid as well as the P/S ratio has effect on hepatic microsomal lipid peroxidation and eicosanoid production, and perilla oil or linolenic acid(n3) might be less effective on
lipid
peroxidation or PG E2 and TX B2 mediated tumor promotion than corn oil or linoleic acid (n6).
This study was performed to investigate effect of dietary protein and calcium levels on cadmium intoxication in rats Adult Sprague-Dawley male rats(245±21g) were blocked into 18 groups of 7 animals according to body weight. Nine experimental
diets
different with protein (40%), 15%, 7%) and calcium(1.3%, 0.6%, 0.1%) levels were prepared. Nine groups of animals were fed each diet with 50ppm cadmium in drinking water, and the other 9 groups without cadmium for 30days.
@ES Results were summarized as follows :
@EN 1) Body weight gain, F. E. R.(Food Efficiency Ratio) and weights of liver, kidney and femur were higher in high protein groups among cadmium exposed groups.
2) Cadmium contents in liver and intestine were higher in rats fed high protein diet or low higher in high protein groups among cadmium excretion was highest in high protein-high calcium diet group among cadmium exposed animals. Metallothionein
contents in liver, kidney and intestine were higher in animals exposed to cadmium and fed high protein diets.
3) Gel filtration chromatography of cytosolic solution showed that the higher dietary protein and calcium levels were. The more cadmium was found in metallothionein fractions.
4) No gross histopathological change was seen in liver, kidney and intestine of cadmium exposed rats. However a significant increase of smooth endoplasmic reticulum, which was alleveated by high protein-high calcium diet, was observed.
Results obtained indicated that not only high protein diet but also high calcium diet showed preventive effect on cadmium intoxication by increasing the induction of metallothionein synthcsis and decreasing the cadmium absorption.
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